We investigate whether election of Donald Trump as the president of the United States of America (the US) and subsequent changes in environmental policies and regulations affected any of the 49 different industry sectors in the US. We analyze 19 different events during Trump's tenure that were mainly rollbacks of previously created regulations and policies. To analyze stock market effects, an event study methodology is used to assess industry reactions. We assume that Trump loosened environmental regulations and policies to strengthen the US economy. Results show that the lax enforcement of environmental regulations and policies was not effective. Only the coal industry can be considered a beneficiary because it experienced repetitive significant positive abnormal returns, whereas other industries experienced mixed or negative reactions or discontinuous positive reactions. Our results contribute to the extant literature on the US environmental policy within the scope of industry.